Electrical switch



April 1934- E. A. RUTENBER ,956,363

ELECTRICAL SWITCH Filed March 25, 1952 INVENTOR ATTORNEY Patented Apr. 24, 1934 UNITED STATES PATENT QFFICE ELECTRICAL SWITCH Application March 25, 1932, Serial No. 601,069

8 Claims.

The present improvements relate in general to electric switches and more particularly to switches of the rotary type, although it will be apparent as the description proceeds, that they are adapted for use with other types of switches as well as with other electrical equipment.

A primary object, among others of the improvements, is to provide a novel switch assembly which will be more efiicient in operation, economical to manufacture and will lend itself to easy and ready replacement of parts.

A further object is to provide an improved switch device which may be conveniently assembled and dismantled. Another object is to provide a novel mounting for the switch, including more durable and separable parts. An improved switch housing including novel insulating means and methods constitute further objects of the invention. n Other objects and advantages will be apparent to those skilled in the art upon reference to the accompanying specification and drawing, in which-- Fig. 1 is a vertical section through a rotary snap switch embodying my invention;

Fig. 2 is a perspective view of the switch mounting partly broken away;

Fig. 3 is a view similar to Fig. 2, illustrating the outer casing or housing;

Figs. 4 to 7 are perspective views of details.

Referring to the drawing, the present improvements are illustrated in association with a novel rotary snap switch of the reversible type, wherein the contacts can be made and broken by rotating the switch in either direction. The switch mechanism comprises a spindle 10 rotatable by handle 11 in either direction. The switch blades 12 are suitably mounted on spindle 10 and are insulated therefrom and from one another by means of discs 13 and 14 of non-conducting material. Plates 15 and 16 connected by studs 17 serve to retain the parts in proper assembled relation.

The upper plate 15 has 2. lug 18 disposed between the ends 19 and 20 of a switch coiled spring 21, which is torsionally stressed by a lug 22 of the spring-housing 23 which is keyed to spindle 10. An escapement mechanism 24, which is operated by the spindle 10, is provided beneath the lower plate 16. One element of this mechanism comprises a plate 25 having upstanding detents 26 which co-operate with a pawl of the escapement mechanism in a well known manner.

A housing or casing 27 illustrated in Fig. 3, is

provided for the switch elements. This housing constitutes a metallic cup shaped member in which the switch elements are securely mounted. It will be seen that this metallic cup afifords a firm foundation for the movable and immovable parts of the assembly.

The base of the metallic cup is perforated at 28, 29 and 30 to permit mounting of the switch parts. As seen in Fig. 1, the spindle 10 extends through perforation while studs 31 in perforations 29 serve to anchor plate 25 to the base of the cup.

Terminal posts 32 are provided within the cup area and have portions extending through perforations 30, and on the under side of the cup these terminals are provided with screws 33 for securing electrical conducting wires thereto.

Since the cup 27 is made of conducting metal, it is essential that the switch and terminal be insulated therefrom. To this end the parts 34, 35 and 36 are provided, see Figs. 4, 6 and 7. All of these three members are made of bakelite or other non-conducting material and serve to com pletely insulate the assembly. Plate or disc member 34 is given the convenient form of an annular ring which forms a nice fit with circular plate 25. These two elements provide an inner bottom for the cup 27.

The circular bakelite disc 35 is provided on the exterior of the cup and is held in position by the terminal posts and their securing means as seen in Fig. 1. As seen in Fig. 6, this disc is equipped with a number of grouped perforations, each group providing a central aperture for the terminal screw, such as 33, and the side apertures accommodating studs or rivets 32A projecting downwarly from posts 32, which serve to secure the bottom of the cup between the bakelite members 34 and 35.

In order to protect the switch and terminals from contact with the interior walls of the metallic cup a bakelite or other insulating lining 36 is provided. This member constitutes a flexible sheet-like strip of non-conducting material (Fig. 7) which is sprung into position and by virtue of its inherent spring action and flexibility, the lining tends to uncoil or open to the condition seen in Fig. 7. It thereby maintains itself in close contact with the inner wall of the cup. The strip therefore tends to hold itself in position. This faculty is supplemented by the size of the annular disc 34, whose diameter is slightly less than the inner diameter of the cup 27, to accommodate the strip 36 in a pocket-like annular space between the cup wall and the disc (Figs. 1 and 2).

This arrangement of parts is such, that the strip is crowded and the disc 34 presses it outwardly against the wall so that the bottom of the strip is held tightly in place. Accordingly, when the disc is fixed in place by rivets 32A, the strip 36 is securely held in position and against dislodgment. This frictional grip method of insuring proper positioning of the bakelite strip 36, contributes materially in facilitating assembly of the device, as well as in reducing manufacturing costs.

A rigid plate 37 spans the upper open face of the cup 27, is swaged into place and provides a mounting for centering the spindle 10. A suitable covering (not shown) is provided between the handle 11 and the top of the cup.

The numerous advantages of the improvements will be apparent. The parts are of convenient size and shape so that their assembly is very easy. Furthermore, the employment of a metallic cup with removable or separable insulating members is of marked importance. Thus departure from the conventional porcelain or other ceramic insulating materials cannot be overemphasized. In former devices, a crack or fracture of U113 ceramic insulating base compelled discarding of the switch unit completely. No fractured part could be removed and a new element provided, thereby afiording salvage of the remaining good parts. The period of usefulness of a unit was therefore uncertain, and the cost of replacement was great. A broken insulating base always required a complete new unit.

The present improvements however provide a very economical assembly. The metallic cup is indestructible and cannot become cracked or broken from causes which would impair a unit made of a ceramic. If any of the parts become damaged or broken, they can readily be replaced and repaired. Manifestly, when a conducting or a non-conductin part is broken or rendered useless, only that particular item need be replaced, while the remainder of the unit is made use of without further cost or replacement. The saving eii'ected is therefore considerable, since the replacement of a broken part, such as disc 34 or 35. is far more inexpensive than the provision of an entire new unit.

virtue of the rigid mounting provided by the present improvements, the efficient operation of the rotary switch itself is not sacrificed. As a matter of fact the spindle 10 is journaled so as to insure efficient functioning even when certain of the parts are broken or damaged. The structure is therefore more than a protective housing, and serves as a block to which the parts may be anchored.

I claim:

1. An electric switch comprising a metallic cup, a rigid web disposed across and fixed to said cup, a rotary switch spindle journalled in said cup and web, an insulated handle for operating said spindle, an insulated bottom for said cup and terminal posts within said cup and extending through the base of the cup and insulated by said bottom.

2. In an electric switch, a circular metallic cup, a spindle rotatably mounted in said cup, a circular insulating disc disposed on the interior bottom of said cup, a circular insulating disc covering the exterior bottom of said cup and terminal posts securing said discs to said cup.

3. In an electric switch, a metallic cup, a spindle rotatably mounted in said cup, an escapement mechanism operated by said spindle and having a portion occupying the center of the cup bottom, an annular insulating member encircling said portion and disposed on the interior bottom of said cup, an insulating disc disposed on the exterior bottom of said cup and terminal posts securing said member and disc to the cup.

4. In an electric switch, a metallic cup, 2. spindle rotatably mounted in said cup, an insulating disc disposed on the interior bottom of said cup, said insulating disc being of less diameter than the diameter of the cup whereby an annular clearance is defined between the periphery of the disc and the sides of the cup, an insulating lining disposed vertically within said annular clearance in said cup the thickness of said lining slightly exceeding the width of said annular clearance whereby the lining is frictionally held in position by said disc, an insulating disc disposed on the exterior bottom of said cup, means for securing said discs to said cup and terminal posts within said cup engaging said interior disc.

5. In an electric appliance, a metallic housing, an insulating lining sprung into position within said housing, an insulating plate within said housing and engaging said lining for frictionally holding same in position, an insulating plate on the exterior of said housing and means for securing said plates to the housing.

6. A non-breakable insulating mounting for electrical units comprising a metallic base and an upstanding metallic wall surrounding said base, an insulating means lining said wall, and means for gripping said insulating means and pressing it in fixed position against said wall without piercing said insulating means.

'7. A non-breakable insulating mounting for electrical units comprising a metallic base and an upstanding metallic wall surrounding said base, an insulating means lining said wall and an insulating member for gripping said insulating means and pressing it in fixed position against said wall.

8. In an electrical appliance, a metallic cup, an insulating disc disposed on the interior bottom of said cup, said insulating disc being of less diameter than the diameter of the cup whereby an annular clearance is defined between the periphery of the disc and the sides of the cup, an insulating lining disposed vertically within said annular clearance in said cup, the thickness oi? said lining slightly exceeding the width of said annular clearance whereby the lining is frictionally held in position by said disc.

EDWIN A. RUTENBER. 

